Impedance-Based Rapid Diagnostic Tool for Single Malaria Parasite Detection

IEEE Trans Biomed Circuits Syst. 2022 Dec;16(6):1325-1336. doi: 10.1109/TBCAS.2022.3215586. Epub 2023 Feb 14.

Abstract

This paper presents a custom, low-cost electronic system specifically designed for rapid and quantitative detection of the malaria parasite in a blood sample. The system exploits the paramagnetic properties of malaria-infected red blood cells (iRBCs) for their magnetophoretic capture on the surface of a silicon chip. A lattice of nickel magnetic micro-concentrators embedded in a silicon substrate concentrates the iRBCs above coplanar gold microelectrodes separated by 3 μm for their detection through an impedance measurement. The sensor is designed for a differential operation to remove the large contribution given by the blood sample. The electronic readout automatically balances the sensor before each experiment and reaches a resolution of 15 ppm in the impedance measurement at 1 MHz allowing a limit of detection of 40 parasite/μl with a capture time of 10 minutes. For better reliability of the results, four sensors are acquired during the same experiment. We demonstrate that the realized platform can also detect a single infected cell in real experimental conditions, measuring human blood infected by Plasmodium falciparum malaria specie.

MeSH terms

  • Animals
  • Electric Impedance
  • Erythrocytes
  • Humans
  • Malaria* / diagnosis
  • Malaria* / parasitology
  • Parasites*
  • Plasmodium falciparum
  • Rapid Diagnostic Tests
  • Reproducibility of Results
  • Silicon

Substances

  • Silicon